A semiconductor chip is electrically connected to the substrate of an electronic device by bonding wires to pads provided on the chip.
When a wire is bonded to a pad, mechanical stress resulting from the bonding is applied to the pad and members under the pad. Not only during the bonding but also during a product test, mechanical stress is applied to the pad and the members under the pad by the probe needle of a tester.
The mechanical stress produced during the bonding and during the test may cause structural damage to the members under the pad, and break (short-circuit) interconnects and crack an interlayer insulating film and contacts.